NO!

A way to interrupt a person who is trying or about to try to make an attempt at something like singing or acting and is doing horribly. Usually said in a deep voice to surprise the person it was said to and make them stop.
Example 1: Your friend sucks at singing and he/she keeps trying
Friend:"You want to hear me..."
Me: "NO!"

Example 2: Your friend copies dance moves ... and makes them look bad
Friend: Watch me do a pin drop!
Me: NO!
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